Electronic vapor provision systems such as e-cigarettes generally contain a reservoir of liquid which is to be vaporized, typically nicotine. When a user inhales on the device, a heater is activated to vaporize a small amount of liquid, which is therefore inhaled by the user.
The use of e-cigarettes in the UK has grown rapidly, and it has been estimated that there are now over a million people using them in the UK.
During the operation of electronic vapor provision systems, the heater may heat the liquid to be vaporized to an extent that some undesirable impurities are formed by the heating. For example, the liquid may be heated to the extent that undesirable aldehyde compounds may be formed. Such compounds may impact on the taste of the inhaled vapor.